Gladiolus papilio

Gladiolus papilio: how do you recognise it?

Habit

A corm about 90 cm tall and 30 cm wide, with straight flower stems; spreads by underground stolons.

Leaves

Narrow and sword-shaped, grey-green, in a fan at the base of the stem.

Flowers

A loose spike of several nodding, almost bell-shaped flowers, grey-green to cream with purple veins and a dark blotch, from August to October.

Corm

A round, flattened corm with a fibrous tunic; it forms stolons and small cormlets.

Dormancy

The leaves disappear in autumn; in winter the corm rests underground.

Flowering: August–October · Plants: April–May

Why grow it?

• Striking nodding flowers in grey-green and purple with a butterfly-like blotch: very different from ordinary gladioli.
• Flowers from August to October, when many borders are looking tired.
• Fairly hardy for a gladiolus: it can stay outdoors and spreads.
• Bees and bumblebees visit the flowers for nectar.
• Looks lovely in a natural, loose border among grasses and late perennials.

Gladiolus papilio: where does it grow best?

• Full sun and a warm, sheltered spot, for example against a south-facing wall.
• Well-drained sandy, loamy or clay soil, neutral to chalky; not too dry in summer, not too wet in winter.
• Normally moist: water regularly in dry weather in summer.
• Sheltered from wind; plant 15–20 cm apart, in groups of at least five corms.

Light

Sun

Soil type

Sand, loam or clay

Acidity

Neutral or chalky

Moisture

Normal

Size

0.9 m tall, 0.3 m wide

Hardiness

Half hardy (to -12 °C): protect it in harsh winters

Goes well with

• Ornamental grasses: Loose grasses such as purple moor grass give the flowers a soft backdrop.
• Michaelmas daisy: Flowers at the same time in blue and purple and suits the colours of the gladiolus.
• Ice plant: A sturdy, late perennial for the same sunny border.
• Japanese anemone: Pink and white flowers in the same late summer.

Gladiolus papilio: when and how to plant it?

Plant in April–May.

1. Plant in April–May, once the hardest frosts are over.
2. Dig a hole 10–15 cm deep: planting deeply makes it hardier.
3. In heavy soil, mix in some coarse sand so that water drains away well.
4. Set the corm pointed end up, 15–20 cm from the next.
5. Cover with soil, firm down and water; then add a layer of mulch.

Care

Watering

Water regularly in dry weather in summer, especially during flowering: in the wild it grows in damp places.

Feeding

In spring, a little compost or a feed for flowering plants; nothing more is needed.

Mulching

A layer of compost or bark keeps the soil moist and protects the corms in winter.

Support

In a windy spot give a small stake so the flower stems do not fall over.

Stolons

Every two or three years, remove excess cormlets if the group gets too large.

Tip: Plant it deep (10–15 cm) and put a thick layer of mulch over it in winter: that makes it fairly hardy and it returns year after year.

Gladiolus papilio: when to prune it?

When: This gladiolus is not pruned. After flowering you cut off the flower stem and, later, the dead leaves, in November.

How:

• Cut off the faded flower stem if you do not want seed.
• Leave the leaves until they are yellow and withered.
• Cut the dead leaves back in November to a few centimetres above the ground.

Caution: Do not cut off the leaves while they are green: the corm needs them to flower again.

Pruning calendar and basic rules

Propagation

Separating cormlets

In spring, just before planting: lift a group, detach the cormlets and stolons and plant them 10–15 cm deep.

Seed

Sow in spring in a pot of sandy compost in a bright, warm place. The seedlings flower after a few years.

Gladiolus papilio: how does it get through the winter?

Hardy to −12 °C: protect in harsh winters.

• Fairly hardy, to about −12 °C: in most Belgian winters it can stay outdoors.
• Put a thick layer of compost or leaf mulch over the corms, especially on heavy, wet soil.
• In areas with hard frosts or on wet clay: lift the corms, let them dry and store them frost-free in dry sand.
• In a pot: put it away dry and frost-free.

Diseases and pests

• Gladiolus thrips: Silvery streaks on the leaves and distorted flowers. Spray with water and cut off affected parts; avoid hot, dry spots.
• Slugs: They eat young shoots in spring. Collect them in the evening or put down a barrier of coarse sand.
• Corm rot: The corm turns soft and brown, especially in wet winters. Provide well-drained soil and store lifted corms dry.
• No flowers: Planted too shallowly, too dry or too crowded. Plant deeper, water and divide the clump.

Through the year

• March: Divide clumps and detach cormlets.
• April: Plant 10–15 cm deep.
• May: Plant. Watch for slugs.
• June: Water in dry weather. Put in stakes.
• July: Water in dry weather. Watch for thrips.
• August: Flowering begins.
• September: Full flower.
• October: Last flowers. Lift the corms if you wish.
• November: Cut back dead leaves and put down a thick layer of mulch.
• December: Dormant.

Edible and useful

Not edible. All parts of gladiolus are poisonous, especially the corms: they can cause vomiting, drooling and diarrhoea, in children as well as in dogs, cats and horses. Gladioli that you lift in autumn, such as the large-flowered garden gladiolus and acidanthera, are stored frost-free until spring, often in the cellar or garage where the potatoes and onions are kept too: their flat corms with a brown papery skin can then be mistaken for shallots or onions. So store them separately, in a labelled box or bag, out of reach of children and pets. Do not leave corms lying where dogs could find them, and wear gloves when lifting, cleaning and planting them. If any is swallowed, call a poison centre (in Belgium 070 245 245) or your doctor at once.

Good for wildlife

Bees

Nectar and pollen for honeybees and wild bees.

Did you know?

• The species name papilio is Latin for ‘butterfly’ and refers to the butterfly-like pattern on the flower.
• Gladiolus comes from the Latin gladius, ‘sword’, after the sword-shaped leaves.
• Unlike many other gladioli, it grows in damp, grassy places in its homeland.